Leading-in wire



HENRIK BOVING, OF NEW YORK, N. Y., ASSIGN'OR TO WESTERN ELECTRIC COMPANY, INCORPORATED, 015 NEW YORK, N. Y., .A. CORPORATION OF NEW YORK.

LEADING-IN WIRE.

No Drawing.

To all whom it may concern:

Be it known that l, HENRIK Bovmo, a citizen of the United States, residing at New York, in the county of New York, State of New York, have invented certain new and useful Improvements in Leading- Tn Wires, of which the following is a full, clear. concise, and exact description.

This invention relates to leading'in wires for incandescent lamps, vacuum tubes, mercury arc rectifiers and the like, and more particularly it relates to a method of coat ing base metal leading-in wires with a fluxing material.

The object of this invention is to produce a leading-in wire having superimposed upon it a flux-containing composition of sufficient elasticity and toughness to withstand any bending or twisting incident to the reeling of the wire.

In making use of iron, iron nickel alloy and copper wires for conducting current through the glass walls of evacuated glass articles, it has been found necessary to employ a fluxing agent in order to secure a satisfactory tight seal. \Vhile the fluxing medium may be applied just prior to the insertion of the wire in the glass, it is highly desirable that a continuous film of the fiux be so attached to the wire as to permit the latter to be reeled, subsequent to the treatment, without danger of disrupting the superimposed coating.

Such a film or coating is produced according to this invention by adding to the flux a suitable gum which, after undergoing a chemical reaction produces a composition capable of forming a hard, continuous layer on a metallic surface. As fluxing medium a borate,for example,borax Na B O -1-1OH O is preferably used. To this concentrated solution is added a predetermined amount of a suitable gum, as, for example, shellac. The chemical action'which ensues appears to be somewhat in the nature of a saponification. The wire to be covered by this composition is first freed from any surface grease or dirt and then passed slowly through the bath. As it comes out of the Specification of Letters Patent,

Patented Nov. 2, 1920.

Application filed November 19, 1919. Serial No. 339,231.

latter the coating is dried in a current of is disintegrated and decomposed, the air furnishing the necessary amount of oxygen for a complete combustion.

While shellac has been mentioned as the gum which is preferred for use in the proc ess, it is to be understood that any gum having the properties of shellac, when used in the manner described above, and any borate having the fluxing properties of borax may be employed.

It may sometimes be desirable to add glycerin to the bath in order to prevent the borax from crystallizing out. Thisaddition would be required where the bath becomes over concentrated due to the loss of water. The presence of the glycerin in the coating will, moreover have a beneficial effect if the wire is tobe stored a considerable length of time after treatment.

lVhat is claimed is:

1. The method of producing a superimposed flux coating on a leading-in wire which consists in drawing the wire through a bath containing a borate and a gum having the properties of shellac and then subjecting it to a current of warm, dry air.

'2. A leading-in wire covered with a composition containing a borate and a gum having the properties of shellac, v

3. A. leading-in Wire covered with a composition containing glycerin, a borate and a gum having the properties of shellac.

t. A leading-in wire covered with a composition containing a borate and shellac.

5. A leading-in wire covered with a composition containing borax and shellac.

In witness whereof, I hereunto subscribe my name this 18th day of November, A. D. 1919.

HENRIK BOVING. 

